Multi-protocol label switching or MPLS is a framework specified by Internet Engineering Task Force (IETF) that provides efficient routing, forwarding and switching traffic flows through a telecommunication network. MPLS allows a mapping of Internet protocol (IP) addresses to fixed length labels used by routers and other equipment to route and switch packets. In MPLS, packets are transmitted on label-switched paths (LSPs), which are specified by a sequence of labels at each node along the path from the source to the destination. LSPs are established prior to packet transmission. The labels are distributed by protocols such as border gateway protocol (BGP). Each data packet encapsulates and carries the labels between the source and the destination. The devices that operate using MPLS can be classified into label edge routers (LERs) and label switching routers (LSRs), which route and switch the data packets at the edge and in the core of the network. Therefore, the MPLS label governs inter-node packet transmission.